The present invention relates to a printed circuit board holding structure for attaching a printed circuit board (PCB, hereinafter) into a housing, and more particularly to a PCB holding structure capable of reducing a thickness of the housing.
Conventionally, there has been a PCB holding structure for attaching a PCB into a housing as shown in FIGS. 4 and 5. The PCB holding structure serves to attach a sub-PCB to a chassis provided in a casing of a mobile telephone. Description will be given below with reference to FIGS. 4 and 5.
As shown in FIG. 4, the mobile telephone comprises a first casing 21 and a second casing 22. The first casing 21 is provided on the back side and accommodates a chassis 25, a main PCB 24 held on the lower side of the chassis 25, a sub-PCB 26 held on the upper side of the chassis 25, and an LCD module 27 held on the upper side of the chassis 25.
The second casing 22 is provided on the surface side to cover the upper surface of the first casing 21 and has an opening formed in a position opposed to the LCD module 27. A transparent window 23 is fixed over the opening. In the following description, an upward direction during the use of the mobile telephone is set to a forward direction of the casing.
On both side ends in a place of the chassis 25 where the sub-PCB 26 is to be attached, a pair of movable clicks 28 and 29 are provided in a longitudinal direction with a predetermined space, respectively. In the movable clicks 28 and 29, taper faces formed on upper ends are opposed to taper faces of the movable clicks 28 and 29 provided on opposite side ends. Moreover, the space between the opposed taper faces is set to be slightly smaller than a lateral width of the sub-PCB 26 and elastic deformation can be carried out in such a direction that the space is increased.
When attaching the sub-PCB 26 onto the chassis 25, the taper faces of the movable clicks 28 and 29 are pressed downward from the lower surfaces in both side edge portions of the sub-PCB 26 as shown in FIG. 5A. The movable clicks 28 and 29 are pressed against the sub-PCB 26 and are thereby deformed elastically in such a direction that the lateral space is increased, and are then returned to an original state after the sub-PCB 26 is mounted on the upper surface of the chassis 25. Thus, the sub-PCB 26 can be held by the movable clicks 28 and 29.
In, the conventional PCB holding structure described above, the sub-PCB 26 is guided and held through the movable clicks 28 and 29. As shown in FIG. 5B, therefore, it is necessary to have a holding width a in addition to a guide width b for guiding the sub-PCB 26 to a predetermined board position. In other words, a width of (a+b) is required for the taper fate and a height of (d1+d2) is required for the taper face. As a result, the taper face of the movable click is increased upward. Consequently, there has been a problem in that a vertical thickness of the casing is increased.
In order to solve such a problem, the invention has an object to provide a PCB holding structure capable of reducing a thickness of a casing.
The present invention provides a PCB holding structure wherein a first guide member having a taper face for guiding a PCB in a transverse direction when fixedly putting the PCB on an attachment object member and a second guide member having at a taper face for downward guiding the PCB put fixedly when sliding the PCB in a longitudinal direction are provided on the attachment object member. By such a structure, it is possible to set the heights of the first and second guide members to be smaller than a height of a conventional click. Therefore, it is possible to reduce a thickness of an apparatus casing having the PCB provided therein.